Warp-tensioning means for looms.



No. 819,742. PATENTBD MAE-{18,1906

W. F. DRAPER. A v WARP TENSIONING MEANS FORJLOOMS.

APPLICATION FILED NOV. 4, 1906.

- UNITED STATES PATENT OFFICE.

WILLIAM F. DRAPER, OF HOPEDALE, MASSACHUSETTS, ASSIGNOR TO DRAPER COMPANY, OF HOPEDALE, MASSACHUSETTS, A CORPORA- TION OF MAINE.

WARP-TENSIONING MEANS FOR LOO MS.

Specification of Letters Patent.

Patented May 8, 1906.

Application filed November 4, 1905- Serial No. 285,844.

sachusetts, have invented an Improvement in Warp-Tensioning Means for Looms, of which the following description, in connection with the accompanying drawings, is a specification, like letters on the drawings representing like parts.

The invention to be hereinafter described relates to looms, and more particularly to the warp controlling or tensioning means therefor, whereby the warp-threads may be woven slack or with very little tension and the resulting product be given good cover Without defects attributable to overshots or breakage of warp-threads.

In weaving fabrics with slack warp-threads or with warp-threads having very little tension it is found that overshots are liable to occurthat is, the shuttle instead of passing between the two shades or planes of the warpthreads forming the shed would at times pass over some of the slack warp-threads in the upper shade or plane, thereby either producing defects due to such overshots or breaking warp-threads.

With these matters in view the general object of the present invention is to provide means whereby overshots and breaking of warp-threads are prevented, while still retaining the advantages due to the incorporation of substantially slack warp-threads into the loom product. I

Generally stated, the present invention consists of means for taking up the slack of the warp-threads in the upper shade or plane of the shed during the flight of the shuttle and giving back such slack at the moment of beat-up, so that at such time the warpthreads may be in appropriate condition to give cover to the cloth.

It has heretofore been proposed to provide warp-tensioning means for looms in, which a double shed is formed for weavin doublefaced fabrics by means of two shutt es simultaneously picked. In such cases one set of warp-threads was raised above and another set depressed below the plane of the fabric, and still another set was maintained in substantially the fabric plane. As a result the last-named set of warp-threads was slack when the two sheds were formed, and the tensioning means simply took up this slack to make the tension on all the warp-threads equal. At the moment of beat up there was tension on all the warp-threads. Likewise, tensioning means have been proposed in looms for weaving a single-ply fabric in which one set of warp-threads was raised and another set maintained substantially horizontal. Here again the tensioning means simply took up the slack of the horizontal set of warp-threads, and at the moment of beat-up all the warp-threads were under tension.

Other suggestions have been made for maintaining different tensions on the sets of warp-threads at the moment of beat-up in order to throw the weft or filling to one or the other surface of ,the fabric. None of these, however, provide for the weaving of cloth with slack warp-threads, nor do they disclose the purpose of taking up the slack in the upper shade or plane of the warp during the picking operation and then giving up such slack at the moment of beat-up, all of p which constitutes the essentials of the present invention to be hereinafter broadly claimed. I

In the accompanying drawings, which disclose one of the many forms the present invention may assume and only so much of a loom structure as is necessary to illustrate its appllcationlthereto, Egure 1 18 a sect onal elevation, parts being broken away, showing the warp controller or tensoning means in one position to take up the slack of the warp in the upper shade or plane of the shed. Fig. 2 is a similar view showing the warp-controller or warp-tensioning means in position to take up the slack of that se t of warpthreads which was before in the lower shade or plane and which by the shedding mechanism has now been placed in the upper shade or plane of the shed. Fig. 3 is a detached plan view of the rear portion of the loom shown in Figs. 1 and 2.

Having reference especially to Figs. 1 and 2, the framework A, the crank-shaft A, the lay A the pitman A the breast-beam A, the whip-roll A cam-shaft A, the heddleframes A A and their appropriate operating means for shedding the warp-threads are andmay be of any usual or preferred form and construction.

The warp-threads (designated as a whole by A are delivered from any suitable source of supply, pass over the whip-roll A and are then split or divided, as usual, and pass alternately over and under lease-rods a a, then through the heddle-frames, the reed of the la and thence to the breast-beam, in all of which respects the structure and arrangement may be as usual, except that the warpthreads are slack or have very little tension.

Owing tothe substantially slack condition of the warp-threads, the shuttle is liable to make overshots .or pass above some of the warp-threads in the upper shade or plane of the shed as said shuttle is picked. Therefore means are herein provided for taking up the slack in warp-threads of the upper shade or plane of the shed during the passage of the shuttle through the shed and thereafter giving up such slack at the moment of beat-up, the effect of which is to prevent such overshots, overcome'breakage of warp-threads, and give cover to the cloth. As one of the many forms of such means the drawings show one of the lease-rods a pivotally mounted in bracket-arms a secured to the loom-frame and provided with a projecting shoulder (L3, extending transversely of the loom the full width of the warp. Secured to one end of the lease-rod a is an arm a, to which is connected an actuator a, which receives motion from the cam-shaft A by means of a crankarm a". From this construct on it w 11 be seen that if the lease-rod a is osc llated in its bearing-arms a? the project .ng shoulder a will be caused to bear first upon one set of warpthreads passing the lease-rod a, then upon the other set of such warp-threads, as illustrated in Figs. 1 and 2, the operation being timed with respect to the shedding mechanism so that when the shed is formed the shoulder a will bear upon the set of warpthreads form ng the upper shade or plane, thereby taking up the slack in such set of warp-threads.

As usual in the character of looms illustrated, the cam-shaft A makes one revolution to each two revolutions of the crankshaft A, and the shuttle is thrown when the lay is in its back pos t on. Referring to Fig. 1, the shed has been formed, the lay is in its back position, and the shuttle is now picked.

At this t'me the lease-rod a is osc'llated by the actuator 0, from the cam-shaft A to cause the shoulder a to depress or bear upon the set of warp-threads b, F g. 1, form'ng the upper shade or plane of the shed, thereby taking up the slack in such set of warp-threads.

In a halfrevolut on of the crankshaft and one-quarter revolution of the cam-shaft the filling or weft thread placed in the shed by slack in order to give cover to the cloth, and

this results from the uarter-revolution of the cam-shaft A, whic oscillates the leaserod (1 to an intermediate position, so that the shoulder a does not act on either set of warpthreads. On the next pick of the shuttle, Fig. 2, the set of warp-threads b, before in the lower shade or plane of the shed, is in the upper shade "or plane of the shed, and the cam-sh aft will have revolved one-half revolution from its position in Fig. 1, thereby turning the lease-rod a into the position shown in Fg. 2, with the shoulder a bearing upon the set of warp-threads b, the slack of which is thus taken up for the passage of the shuttle. On the beat-up the cam-shaft W111 have made three-quarters of a revolution, thereby carrying the lease-rod a to an intermediate position, as before, and giving up the slack to the set of warp-threads b in the upper shade or plane of the shed.

While the drawings illustrate and the specification describes the warp controller or tensioni'ng means as comprising aparticular construction of one of the lease-rods with means for actuat ng it, it is to be understood that this is merely one of the many forms in which the present invention may be embodied, and it is to be understood that the essentials of the invention, irrespective of mechan cal details, reside in means for taking up the slack in the upper shade or plane of the shed during the flight of the shuttle and for giving back such slack at the moment of beat-up.

Having thus described my invention, what I claim, and desire to secure by Letters Patent, is

1. In a loom for weaving with slack warpthreads, the combination of the lay and sheddng mechanism, of means for t ghtening or tak ng up the slack of the warp-threads in the upper shade or plane of the shedduring the picking operaton and for slackening the warp-threads in said plane of the shed during the beat-up.

2. In a loom for weaving with slack warpthreads, the combinaton of the lay and sheddng mechan sm. of means for holding the warp-threads in the upper shade or plane of the shed taut during the pick ng operation and for slackening sa d warp-threads in the upper shade or plane of the shed during the beat-up.

In test mony whereof I have s gned my name to th s specification in the presence of two subscrlb'ng w'tnesses.

- WILLIAM F. DRAPER Witnesses:

GEORGE OTIS DRAPER, ERNEST W. W001), 

